Proportion Explosion

Since we are spiralling the curriculum in grade 9 applied, my math task choice is getting very picky! I always want to uncover more that one expectation in a lesson/task! In this task we used volume of spheres, solving proportions, and properties of linear relations.

Act 1:

We took questions and wonderings and then settled on the problem of Let’s see that balloon explode and when is that going to happen?
We guessed and recorded the guesses on our whiteboard for future comparisons!

Act 2: What will we need!

There were good conversations on this piece! I’m always surprised by how much kids know! Someone asked for the rate of water!!!! Wowsers! I assumed I might have to dig to get them to ask for that one. They also wanted me to say how much a balloon will hold…..which is where I wanted to direct them first.

Info to give and record:

As always, I made them guess for it! After revealing 12 inches….we converted to centimeters. Next it was their turn to go ahead and find the volume of the balloon. I find it so valuable to have discussions on why use a sphere to model the volume? Will we be correct? Is it ok we’re wrong?

Volume of the sphere/balloon

Act 2: Rate of Water

This is where the kids got lost a bit! They weren’t sure how to use this part exactly after just finding the volume of the balloon.  I stepped in and used some direct instruction on how to set up the proportion. Handout prepared:


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Act 3: The reveal

The extension is how we practiced solving a few proportions. We solved for the volume when the time was 10 seconds, 20 seconds, until kids saw the pattern.

10 seconds

10 seconds

After filling the table out, we found the first differences, discussed direct vs. partial linear relations!

Grab all the files to run in your class:

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Distance-Time Graphs – Gallery Walk

The last few semesters I ran this two-day lesson on distance-time graphs. Today I added a new twist on Day 2.

Recap: Day 1 – A few prediction videos on water height in a cup vs. time. Then WATERLINE by Desmos!

Day 2:  Today

Warm Up – We reviewed the previous day’s work by choosing one of the cups from the picture and drawing a water-height vs. time graph.

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Not surprisingly, no students chose to draw the graph for the Stanley Cup. After they make their sketches we dove into using the CBR Rangers from Vernier just like on Day 2 from the previous post. They walked in front of the Ranger taking various different walks and we all saw their distance-time graphs in real-time. For each walk the students made prediction graphs on their whiteboards before seeing the live graph.

I wanted more predictions from them so I showed them a video I made. They were to watch the video and make a prediction graph of my distance away from the camera vs. time.

After take up of this graph they were to create their own video on the iPads. Each pair of students we’re given a scenario to film that described motion.

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Here are two motion videos they filmed: Very basic to start!

They had to create their distance-time graph and hide it under the flap on the vertical whiteboards.

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Pairs then went on a gallery walk. They watched each student made video, graphed the matching distance-time graph and then checked the answer under the flap.

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Kids enjoyed it and they practiced lots of different distance-time graphs.

Thanks for reading!!!


Knot Again!

I am loving Alex Overwijk’s Knot activity more and more.
Go ahead and read about it!

Ropes of Different Thickness & Equal Lengths

I’m a huge advocate for having kids get their hands dirty and try things out. This one is particularly awesome because students get to experience how the rope length changes. They get to feel and create that change.

For those of you who don’t have ropes….or use this after the activity as part of a consolidation.
Problem 1- Solving a linear equation.
Act 1

Knot Again! Act 1 from jon orr on Vimeo.

Act 2
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Act 3

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Spiralling grade 9 applied math

So, I’m going to spiral the grade 9 applied course! I’m a little hesitant because I’ve taught this course with a units approach for the last 10 years. But I’m also exited!!! It seems so awesome that everyday we will solve problems; Alex Overwijk says

learn to uncover curriculum instead of cover curriculum

Instead of “boring up” the first day with paper and expectations, and policy, etc, etc we talked about being curious, collaborative, creative, and embracing challenge!

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So….we dove right in to this.

Act 1: Showed this:


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